As some may recall, I built a B5 Audi A4 RS4 Sedan.

The B5 RS4 was only available as an Avant (estate / wagon) and I wanted the looks, but without the estate body.
The body work was completed, but my car still had the stock 150hp 2,6L V6 12V, coupled to a 5-speed manual.

Something clearly needed to be done, so Outlaw had the go to match the show! I opted for a 4,2L V8 32V, out of a '98 Audi S8. This produces 340hp in stock form. Mine is also mated to a 6-speed manual tranny.

As this engine is going to be boosted next year, by means of an Eaton M112 supercharger, I chose not to use the original Audi S8 ECU and wiring harness, as it will not give the power required with any form of forced induction. To modify the eprom requires a lot of work, it's all in binary code, and not user friendly at all. After all the time and effort invested, it'll still be lacking.

I opted to go with a stand alone management system, and VEMS fitted the bill. Mapping via the serial port and a laptop would be a doddle, and it employs a MAP sensor, so no need to rely on a restrictive MAF. It also supports Bosch LC1 wide band lambda, which is invaluable when it comes to mapping.

This is my base car:

Hey, Sienna

Just saw d pix in your profile.

Has anyone told you, dat u look so much like my favorite sprinter - Tyson Gay ! ! !

Nice pix though

Thursday morning July 2nd, Outlaw was reversed into position in my garage, for surgery to commence. This was the last time she moved under V6 12V power, and a 5-speed manual tranny. Mileage will be frozen at 220,200+.

The conversion marks the end of the original mechanical parts that came from the factory - as far as bodywork goes, the only OEM panel left is the roof.

Parts being replaced are:

Engine (S8 4,2L V8).
Tranny ('01 B5 S4 DSY 01E 6-speed).
Front driveshafts (B5 RS4).
Rear driveshafts (B5 2,8Q 30V, brand new from Audi).
Propshaft (B5 RS4).
Clutch (B5 RS4).
Flywheel (DVG-V8 S/M).
Front uprights (B5 RS4).
Front suspension upper arms (B5 RS4).
Front suspension lower arms (B5 RS4).
PAS rack (replacement Sport unit).
PAS pump (S8).

Mileage as she stood then:



Asthmatic ABC 2,6L V6, has stood the test of time - who said high mileage cars were bad? Underpowered, but reliable.

pak:

Hey, Sienna

Just saw d pix in your profile.

Has anyone told you, dat u look so much like my favorite sprinter - Tyson Gay ! ! !

Nice pix though

Thanks bud.

No going back now - I tore into her, so she isn't going to turn a wheel under V6 power, ever!


Surprising how much marries together - even the fuel lines are compatible, as well as the PAS hoses, using a 1,8T high-pressure line. The vane pump is in the same place on the S8 engine - lower passenger side. I thought I'd be looking at custom pipework, but clearly not the case.

Unlike the vane pump on the V6 models, whereby it sits in the "V". If I didn't have 1,8T bits lying around, it would have been a headache sorting the PAS hoses out.

I was too tired to take pictures that day.

Strangely, I looked forward more to the engine and tranny swap, as opposed to the leaking PAS rack change. It had been leaking for months, a nasty job to tackle with the engine in situ.

Tear down began at 10:30 am:







V6 out, still got to remove the old 5-speed manual:





5-speed manual removed:



6-speed manual tranny installed:

S8 4,2L V8 engine thrown in:

I spent a whole day, and most of the night, working on Outlaw. In the course of the S8 / 6-speed tranny conversion, I came across quite a few pleasant surprises.

Is the B5 1,8T PAS pipework compatible with the S8 vane pump location? Yes.
Is the B5 1,8T vane pump compatible with the S8's bracket? Yes.
Is the B5 V6 gas pedal cable compatible with the S8 quadrant? Yes.
Are the B5 V6 fuel lines compatible with the AHC S8 motor? Yes.
Are the B5 V6 12V catalysts compatible with the S8 AHC manifolds? Yes.

So far, progress has been good. What's been done:

01E DSY 6-speed tranny installed.
S8 AHC engine fitted.
OEM clutch slave cylinder fitted, all working.
PAS rack replaced - original was leaking.
S4 6-speed selector mechanism fitted, all gears engage.
B5 1,8T vane pump fitted, and plumbed in.
Heater hoses fitted.
B5 V6 airbox fitted.
VEMS stand-alone wiring harness fitted.
S8 starter motor fitted, using original B5 V6 connections, engine cranks fine.
B5 V6 gas pedal cable fitted, works fine.

Just come in for a breather, then next step is to fit the B5 RS4 propshaft.

Integrating the VEMS harness with the B5 is easy, more on that later.

View from underneath:

01E 6-speed manual tranny:



B5 RS4 propshaft - needed, as the 6-speed tranny is longer, so the propshaft had to be correspondingly shorter:





Deltavag custom engine mounts:

And then this was the result:











Now she deserves these badges:

First start-up video - I had a worn camshaft chain on the left-hand bank of cylinders, so was noisy. Been replaced now. It would also not rev above 3,000 rpm, soon found out I'd plumbed the fuel pressure regulator into the wrong vacuum source, all rectified now:



A bit more tweaking, and getting there - she revs freely now:

Sienna that was fantastic! did you replace the ecu's or did a tuning. please enlighteen us on that. any adapations bla bla bla

I didn't need to do any adaptation, as I didn't use the stock Audi S8 ECU.

I opted for full stand alone, which is fully mappable via serial port and laptop.

kablooee:

Sienna that was fantastic! did you replace the ecu's or did a tuning. please enlighteen us on that. any adapations bla bla bla

Ade where have you being? I am still waiting for the remote to the Acura and also get a spare key for it. Holla at me when you are set to do it.

I thought you were addressing me, was a bit confuzzled.

Some of the parts that went into Outlaw's build:

Deltavag custom engine mounts:





OEM VAG Coilpacks:



Mocal 13-row transmission oil cooler:



Audi S8 engine - 4,2L V8 32V:



Bosch red top injectors - 400cc / min @ 3,0 bar:



Deltavag custom flywheel:



, With Audi RS4 B5 clutch:

Outlaw will be making her official debut soon - it's winter, so will be demonstrating the virtues of quattro^TM combined with the beefy torque of the high-output V8 motor.

Videos will be posted.

Powered by Naija!

Prior to Outlaw's successful V8 transplant, there were some other V8 converted Audi A4 B5's, both good and bad. Below are a few.

Firstly, back in 1998, Audi were contemplating the next Audi S4. The B5-based car was a 2,7L V6 30V Biturbo, developing 265hp in stock form. The Forthcoming B6-based S4 was going to be a 4,2L V8 40V, developing 344hp in naturally-aspirated form. So, the outgoing B5-based car was used as a test bed to see how the existing 4,2L V8 from the Audi S8 would fit.

A brand new Audi S4 B5 was supplied by Audi UK, as the R& car. And Audi's then newly acquired subsidiary, Cosworth Technology (now known as Mahle Powertrain) was entrusted with the job of fitting the V8 from a 1999 Audi S8 into the engine bay.

The results were not great, the engine sat so far forward, the front panel had to be cut, locating the radiator further forward, to provide more space. It also meant the hood, bumper, grille and fenders had to be radically altered, to give the desired clearance. The result? An S4 B5, with a functional 4,2L V8 transplant, which was however far from pretty:



For comparison, my own car, prior to my V8 conversion. Note the front panel (radiator support) in it's original form, the grille is of course in it's normal location, i.e in the hood. I took the shot from a similar angle, to give a clearer picture of what was changed in the white car above, to get the V8 to fit:



The next picture shows another A4 B5 V8 conversion. This conversion utilized a different block, the 4,2L V8 40V from the B6-based S4. It was shorter than the earlier block used in the S8. This was achieved by deleting the timing belt from the front, and the camshafts are now chain-driven, with the drive at the rear of the engine. This was done, because the B6-based A4 / S4 range has a shorter hood, and would be unlikely to accommodate the earlier longer V8 block.

This car is based in Canada. It is also a much neater install than the one carried out by Cosworth Technology, and retains the original front section:



The next conversion, to my knowledge hasn't been completed. The base car is a B5-based Audi A4 quattro.

The owner chose to fit the 4,2L V8 40V Biturbo, fom the C5-based Audi RS6. This engine is pretty unique, in that it was automatic only, there was never a manual version, so fitting it to a manual tranny involved making a thick adapter plate. Which in turn meant, whilst the engine sits so far forwards, the builder also had to fabricate aluminium spacers between the chassis rails, and front frame / bumper brackets, to allow for the engine's added length, made worse by the use of the engine-to-manual transmission adapter.

No way would the stock fenders, hood, grille and bumper accommodate the extra length! Last I heard, back in 2007, the owner, a Greek guy was talking of extending the hood, fenders and bumper to fit. It will be interesting to see how it all pans out, though I for one fear it will make the car look very clumsy. All that forward mass will also affect handling, making the car very prone to understeer.

RS6 4,2L V8 40V Biturbo stuffed into the B5 engine bay:





Profile shot: Note how far forwards of the fenders the engine protrudes - how will the headlamps fit?





It's a tight squeeze - even with the coolant expansion tank relocated to the scuttle area:





Underside shot. Note the thick aluminium adapter, between the engine and transmission, the source of the ill-fitting issues:

very good job bro!!! I wanna be like you when I grow up. . .[s]dash me dat ya car now; make you build anoda one[/s]

great job. . . but seriously, i wish i owned your Audi.

Thanks buddy.

nice job u did there, i'm so impressed. i am an auto freak and infact i look forward to owning an auto workshop later on where we can do a lot of after factory pimps and alterations. u r my man.

Thanks, Michael.

I imagine Nigeria's long overdue for aftermarket car care.

yes you are right, i don't mind if we can work something out towards that

michaelala:

yes you are right, i don't mind if we can work something out towards that

Possibly.

What do you have in mind?

a complete workshop where you can love-vendor, repair and perfect our car, a kind of auto lab

That's what I have in mind - please post comments / suggestions here:

https://www.nairaland.com/nigeria/topic-352214.0.html

ok i will

I no know much about cars, but I think that for you to fabricate a custom motor mount this conversion is not common(probably for a reason).
The exhaust still sounds funny(not as smooth as expected, maybe your V6 exhaust is too small, you may have to upgrade for better expiration.

One more question, will the drivetrain on that withstand the additional torque of the V8 considering its original configuration(chassis)

sultaan:

I no know much about cars, but I think that for you to fabricate a custom motor mount this conversion is not common(probably for a reason).
The exhaust still sounds funny(not as smooth as expected, maybe your V6 exhaust is too small, you may have to upgrade for better expiration.

One more question, will the drivetrain on that withstand the additional torque of the V8 considering its original configuration(chassis)

The V6 exhaust is fine, the twin catalyst flexi joints at the front are both split, so leaking. Sounds heaps better with the new replacements.

Cellphone videos also won't capture the true sound as in real life.

The drivetrain is off the B5 RS4 (6-speed) including the rear differential. The 6-speed tranny was an option in Europe on the S8, and bar slightly different ratios, is no different to that fitted to my car. There are also RS4's running in excess of 800hp / 750Nm torque with no adverse issues.

sultaan:

I no know much about cars, but I think that for you to fabricate a custom motor mount this conversion is not common(probably for a reason).

Any alien installation requires fabrication of key components.

The fact mine is not a "normal" conversion, means my car remains unique - besides the blue one I converted for a client (elsewhere in this section) there are no others in Britain.

I alone also hold the blueprints to the brackets and flywheel, of which I have sold several sets to Audi A4 B5 owners in the United States.

Cosworth were the first to do this V8 conversion on a B5 chassis many years ago has a project for Audi to see what they needed to do for the B6 A4 chassis, then came yours years later.

I agree, Doc, and I gave credit to Cosworth Technology further up this page.